Sex of plants, can be manufactured?

I have a little book called "Hydroponically speaking, Cloning" written by Steven Carruthers.
I have just been reading through it because i plan to take quite a few clones from my next grow.
I got to a section called 'Plant Regulators' where it reads:-
When a clone is forming flowers or fruit as a reaction to the change in the light cycle, it is especially susceptible to outside influences regarding its sexuality. When ETHRYL is applied, which the plant recognises as a female hormone, the scales are tipped in favour of femaleness, and then the plant itself starts to produce the hormone on its own to maintain sexual stability.
A fruiting plant will produce its own ethylene naturally.
The application of ETHRYL will not cause sexual reversal. However, a male oriented clone, if caught at the proper time will suddenly have its youthful sexual hormonal ratios altered toward feminization and will proceed along that path. It too will begin to make its own ethylene just like a natural female in order to maintain the hormonal inertia. Sometimes clones get a little confused by all this and end up hermaphroditic, but that only happens to a small number of plants.

So, basically this guy is saying you can almost certainly change a male clone to female if given ETHRYL at the right time..?

What do you all think about this?

A hermie yes because a hermie is both a male and female. Once its sex is determined as male it's set if stone. You can stop it from producing pollen but you can't change its sex.

By the time you cut a clone the sex is inherited from the plant it was taken from. That is the whole idea behind cloning. Exact copy from the plant it was taken from. I don't think you can just cut a male and turn it female.

Sex is determined at the RNA level and not the DNA level of this plant. That is why they can turn hermie and self pollinate to survive.

I can't say I have tried this but will all my experience I say you can't change the sex once it is set in the plants nature. You can deny the plant many tings but changing the sex on the fly is something I don't think we can do at this point in our understanding. I think he is talking more about stabilizing female clones or making feminized seeds maybe?

ive heard this method a few times an i think it does work its also used jus to help garuntee a higher number of females when grown from seed but i dont really like the idea of adding hormones an stuff.
i doubt its got to do with feminized seeds as thats a different process which deosnt have to involve any hormones unless you need mass production of female pollen then it wouldnt be ethryl you would add.
its kinda like giving a human male oestrogen in the way that a bloke would grow tits an other freeaky shit but with plants cos they can produce either male or female plants anyway the process is bit simpler so we jus usually get male or female with the ocasional hermie, in humans you would always end up with a hermie human it would not be physically possible to change man in to a fully fleged woman with jus hormones as are sex is determined from the moment were are conceived, plants however arnt and so can go either way hence makeing sex reversal with the adittion of hormones or sometimes jus undue stress is to some extent actually possible
hope this awnsers it for ya

The 'feminising' soaks and treatments on the market are snake oil. I've tried one- Sensa Soak- what a crock.
If 'feminized' is REALLY important to you, go with fem seeds... otherwise, try the things that PROMOTE females, such as blue light very early in the seedling stage. Try out the 'Ott Light' as a good cheap source of blue spectrum light to supplement your regular flouros during the seedling stage.

CARBOHYDRATE-NITROGEN RATIOS WITH RESPECT TO THE SEXUAL EXPRESSION OF HEMP